316/316L (UNS S31600 / S31603)

Mellow inventory includes 316/316L (UNS S31600 / S31603), in sheet, sheet coil, plate, plate coil, bar, structural and tubular products.Generally, this grade is dual-certified to meet both 316 and 316L. Alloy 316/316L is ideally suited for applications requiring corrosion resistance superior to Type 304 and has good elevated temperature strength.

Corrosion Resistance:

● Generally more resistant than 304 in range of atmospheric environments and many corrosive media due to the increased chromium and molybdenum content.

● Subject to pitting and crevice corrosion in warm chloride environments, and to stress corrosion cracking above about 122°F (50°C).

● Considered resistant to potable water with up to about 1000mg/L chlorides at ambient temperatures, reducing to about 500mg/L at 140°F (60°C).

● Usually regarded as the “marine grade stainless steel” – but is not resistant to warm sea water.

Heat Resistance:

● Good oxidation resistance in intermittent service to 1600°F (870°C) and in continuous service to 1700°F (925°C)

● Grade 316L is more resistant to carbide precipitation.

Applications:

● Food preparation equipment, especially in chloride environments

● Chemical processing, equipment

● Laboratory benches and equipment

● Rubber, plastics, pulp & paper machinery

● Pollution control equipment

● Boat fittings, value and pump trim

● Heat exchangers

● Pharmaceutical and textile industries

● Condensers, evaporators and tanks

321/321H Stainless Steel

Mellow inventory now includes Alloy 321 (UNS S32100) in sheet, sheet coil, plate, round bar, processed flat bar and tubular products.

Corrosion Resistance:

● exhibits good general corrosion resistance that is comparable to 304.

● developed for use in the chromium carbide precipitation range of 1800 – 1500°F (427 – 816°C) .

● can be used in most diluted organic acids at moderate temperatures .

● can be used in pure phosphoric acid at lower temperatures.

● can be used in up to 10% diluted solutions at elevated temperatures.

● resists polythionic acid stress corrosion cracking in hydrocarbon service.

● utilized in chloride or fluoride free caustic solutions at moderate temperatures.

● does not perform well in chloride solutions, even in small concentrations, or in sulfuric acid service.

Applications:

● Aerospace – piston engine manifolds

● Chemical Processing

● Expansion Joints

● Food Processing – equipment and storage

● Petroleum Refining – polythionic acid service

● Waste Treatment – thermal oxidizers

310/S Stainless Steel

Mellow inventory now includes 310/ 310S Plate and Processed Flat Bar (Alloy 310 UNS S31000 / Alloy 310S UNS S31008), ideally suited for high-temperature applications such as heat treatment and chemical processing equipment.

Corrosion Resistance:

● Provides excellent corrosion resistance

● High chromium content allows for good aqueous corrosion resistance

● Excellent resistance at normal temperatures and also has good resistance to oxidizing and carburizing atmospheres

Heat Resistance:

● Good resistance to oxidation in intermittent service in air at temperatures up to 1040°C and 1150°C in continuous service.

● Good resistance to thermal fatigue and cyclic heating.

● Widely used where sulphur dioxide gas is encountered at elevated temperatures.

● Continuous use in 425-860°C range not recommended due to carbide precipitation, if subsequent aqueous corrosion resistance is needed.

● Generally used at temperatures starting from about 800 or 900°C – above the temperatures at which 304H and 321 are effective.

Applications:

● Furnace Parts

● Oil Burner Parts

● Heat Exchangers

● Welding Filler Wire and Electrodes

● Annealing Covers

● Combustion Tubes

● Fire Box Sheets